[11.02] DIRECT Distances to Nearby Galaxies Using Detached Eclipsing Binaries and Cepheids. Results for the Inner part of M33.

The DIRECT project has obtained a total of 170 nights on the FLWO
1.2-meter
telescope and 35 nights on the MDM 1.3-meter telescope from 1996 to
1999 to
search for detached eclipsing binaries and Cepheids in the M31 and M33
galaxies. This is the first step in an ongoing program to improve the
direct
distance estimate to these two important galaxies in the cosmological
distance
ladder. Detached eclipsing binaries provide us with the potential to
determine
these distances with an accuracy better than 5% and possibly to better
than
1%. The massive photometry provides us with good light curves for
known and
new Cepheid variables. These are essential to derive direct
Baade-Wesselink
distances to the galaxies. With both Cepheids and eclipsing binaries,
the
distance estimates will be free of any intermediate steps.

We present the variables found in the inner part of M33, the resulting
Cepheid
P-L relations, and a new distance determination to this galaxy.
Future
work
on outer fields of this galaxy will be combined with the present
results to
arrive at a new determination of the effects of metallicity in the
Cepheid
P-L
relation.